Summary

If you have a 6mm socket of some sort already available, there are certainly better devices available here on thingiverse to insert and remove a nozzle. And for about ten dollars, I bought a cheap "palm ratchet" on Amazon for this purpose. However, this is an easy and much cheaper solution, a 3D printer build of simplicity. I suppose you could make it from some high temp. filament or SLA goop that would withstand up to 220 degrees, I just made this one from PLA. That means you cannot use it to remove a nozzle from an already hot hot-end. Nonetheless, for most other applications, this is all you need to insert and remove nozzles. The knurl turned out nicely with a minimum compile time in Openscad. I used a raft, no supports, and 85% infil. I had looked on Thingiverse first for finding something like it and didn't see what I was looking for. Hopefully, this will get you where you want to go.